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What to do when your dryer duct is too far away to terminate

jar546

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Messages
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You do this of course. Remember when......

IMG_9906.JPG
 
That's a commercial smoothie maker. you have the pic turned 90 degrees too far.
 
This problem starts with design, let's see, where should I draw in the washer/dryer closet, I know, how bout in the the middle of the house in the hallway, ya thats it!
 
* * * *

Shouldn't the paper on that thermal insulation overlap on to the individual

joist / studs and be attached to them?.....Also, shouldn't the lengths of

insulation be one continuous length?

* * * *
 
Last edited by a moderator:
north star said:
* * * *Shouldn't the paper on that thermal insulation overlap on to the individual

joist / studs and be attached to them?.....Also, shouldn't the lengths of

insulation be one continuous length?

* * * *
Absolutely not. The paper is never required to cover the face/edge of the joist/stud. Except for the joist bay that has the fan in it, the others are installed upside-down anyway.
 
* * * *

Jeff,

In reading some of the manufacturer's literature, the thermal insulation

can be inserted in to the individual cavities or stapled to the framing

( see the attached link to Johns-Manville - Installation Guide for one

of their products ).

http://www.specjm.com/files/pdf/bid0016.pdf

3110_e.jpg


* * * *
 
Dryer booster fans are not specified as an option for length limitations in the 2009 IRC. (I suppose if you had manufacturers specs for the dryer that allowed it) The booster fan was included in the 2003 IRC, but went away in the 2006 IRC, was never in the IMC. And, I never did find one that was fully listed in the US, the motors were, not the assembly.
 
north star said:
* * * *Jeff,

In reading some of the manufacturer's literature, the thermal insulation

can be inserted in to the individual cavities or stapled to the framing

( see the attached link to Johns-Manville - Installation Guide for one

of their products ).

http://www.specjm.com/files/pdf/bid0016.pdf

3110_e.jpg


* * * *
It can be but the code does not require it. Drywall contractors who glue an screw will hate you if you do it.
 
$ $ $ $

It can be but the code does not require it. Drywall contractors who glue an screw will hate you if you do it.
That ship has already sailed! :D $ $ $ $
 
here the paper cannot be left exposed for fire danger reasons. read the warning on the facing sometime. our energy code says to staple the facing to the face of the stud/joist for optimum energy performance.
 
The OP appears to be of a floor cavity, not a wall cavity. Excepting manufactured housing, the insulation in a floor cavity is vitually always installed after the subfloor, and the kraft face, even when installed correctly, rarely will overlap the top of the joists.

Is the OP showing a floor or ceiling cavity? If a ceiling cavity, the reverse backing only applys to the cavity containing the vent.
 
Blame it on the architects who always want the laundry room in the middle of the McHouse.

Also, manufacturer's specs can get 'em off the hook, no?

One I wrote up produced documents stating THEIR dryer would push the lint etc 40+ feet.
 
Also, manufacturer's specs can get 'em off the hook, no?
Yes

2009 IRC

M1502.4.4.2 Manufacturer's instructions.

The size and maximum length of the exhaust duct shall be determined by the dryer manufacturer's installation instructions. The code official shall be provided with a copy of the installation instructions for the make and model of the dryer at the concealment inspection. In the absence of fitting equivalent length calculations from the clothes dryer manufacturer, Table M1502.4.4.1 shall be used.
 
Yes, and I was tongue-in-cheek suggesting a manufacturers spec may allow the use of a booster, I seriously doubt it, but was just sayin.........
 
Personally I really hate that addition to the code. There is no way to ensure that future owners of the house will have a dryer with the same capacity. Or for that matter when the existing owners replace said dryer.
 
The nailing of kraft paper to the insides of studs is a convenience to the drywallers, but a detriment to the longevity of the building. Air, spelled m-o-i-s-t-u-r-e moves through those spaces causing problems... As infrequently as all other details get done correctly, like cutting around boxes, etc it's hard to get anyone to understand this one.
 
fiddler said:
Personally I really hate that addition to the code. There is no way to ensure that future owners of the house will have a dryer with the same capacity. Or for that matter when the existing owners replace said dryer.
I don't like it either but like most products it will have a warning label about as effective as "Danger Will Robinson Danger"

M1502.4.5 Length identification.

Where the exhaust duct is concealed within the building construction, the equivalent length of the exhaust duct shall be identified on a permanent label or tag. The label or tag shall be located within 6 feet (1829 mm) of the exhaust duct connection.
 
jar546 said:
You can look at it that way to give the perception that it is not a big deal.5% of the total fires IS a big number and can be preventable. That is the reality. I would think most of these issues are maintenance related.
I did not say that was a good or bad number. Zero would be a good number.
 
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